1*4882a593Smuzhiyun // SPDX-License-Identifier: GPL-2.0+
2*4882a593Smuzhiyun /*
3*4882a593Smuzhiyun * Copyright (C) 2020 Linaro Limited.
4*4882a593Smuzhiyun */
5*4882a593Smuzhiyun
6*4882a593Smuzhiyun #include <common.h>
7*4882a593Smuzhiyun #include <dm.h>
8*4882a593Smuzhiyun #include <dm/device_compat.h>
9*4882a593Smuzhiyun #include <errno.h>
10*4882a593Smuzhiyun #include <mailbox.h>
11*4882a593Smuzhiyun #include <scmi_agent.h>
12*4882a593Smuzhiyun #include <scmi_agent-uclass.h>
13*4882a593Smuzhiyun #include <dm/devres.h>
14*4882a593Smuzhiyun #include <linux/compat.h>
15*4882a593Smuzhiyun
16*4882a593Smuzhiyun #include "smt.h"
17*4882a593Smuzhiyun
18*4882a593Smuzhiyun #define TIMEOUT_US_10MS 10000
19*4882a593Smuzhiyun
20*4882a593Smuzhiyun /**
21*4882a593Smuzhiyun * struct scmi_mbox_channel - Description of an SCMI mailbox transport
22*4882a593Smuzhiyun * @smt: Shared memory buffer
23*4882a593Smuzhiyun * @mbox: Mailbox channel description
24*4882a593Smuzhiyun * @timeout_us: Timeout in microseconds for the mailbox transfer
25*4882a593Smuzhiyun */
26*4882a593Smuzhiyun struct scmi_mbox_channel {
27*4882a593Smuzhiyun struct scmi_smt smt;
28*4882a593Smuzhiyun struct mbox_chan mbox;
29*4882a593Smuzhiyun ulong timeout_us;
30*4882a593Smuzhiyun };
31*4882a593Smuzhiyun
scmi_mbox_process_msg(struct udevice * dev,struct scmi_msg * msg)32*4882a593Smuzhiyun static int scmi_mbox_process_msg(struct udevice *dev, struct scmi_msg *msg)
33*4882a593Smuzhiyun {
34*4882a593Smuzhiyun struct scmi_mbox_channel *chan = dev_get_priv(dev);
35*4882a593Smuzhiyun int ret;
36*4882a593Smuzhiyun
37*4882a593Smuzhiyun ret = scmi_write_msg_to_smt(dev, &chan->smt, msg);
38*4882a593Smuzhiyun if (ret)
39*4882a593Smuzhiyun return ret;
40*4882a593Smuzhiyun
41*4882a593Smuzhiyun /* Give shm addr to mbox in case it is meaningful */
42*4882a593Smuzhiyun ret = mbox_send(&chan->mbox, chan->smt.buf);
43*4882a593Smuzhiyun if (ret) {
44*4882a593Smuzhiyun dev_err(dev, "Message send failed: %d\n", ret);
45*4882a593Smuzhiyun goto out;
46*4882a593Smuzhiyun }
47*4882a593Smuzhiyun
48*4882a593Smuzhiyun /* Receive the response */
49*4882a593Smuzhiyun ret = mbox_recv(&chan->mbox, chan->smt.buf, chan->timeout_us);
50*4882a593Smuzhiyun if (ret) {
51*4882a593Smuzhiyun dev_err(dev, "Response failed: %d, abort\n", ret);
52*4882a593Smuzhiyun goto out;
53*4882a593Smuzhiyun }
54*4882a593Smuzhiyun
55*4882a593Smuzhiyun ret = scmi_read_resp_from_smt(dev, &chan->smt, msg);
56*4882a593Smuzhiyun
57*4882a593Smuzhiyun out:
58*4882a593Smuzhiyun scmi_clear_smt_channel(&chan->smt);
59*4882a593Smuzhiyun
60*4882a593Smuzhiyun return ret;
61*4882a593Smuzhiyun }
62*4882a593Smuzhiyun
scmi_mbox_probe(struct udevice * dev)63*4882a593Smuzhiyun int scmi_mbox_probe(struct udevice *dev)
64*4882a593Smuzhiyun {
65*4882a593Smuzhiyun struct scmi_mbox_channel *chan = dev_get_priv(dev);
66*4882a593Smuzhiyun int ret;
67*4882a593Smuzhiyun
68*4882a593Smuzhiyun chan->timeout_us = TIMEOUT_US_10MS;
69*4882a593Smuzhiyun
70*4882a593Smuzhiyun ret = mbox_get_by_index(dev, 0, &chan->mbox);
71*4882a593Smuzhiyun if (ret) {
72*4882a593Smuzhiyun dev_err(dev, "Failed to find mailbox: %d\n", ret);
73*4882a593Smuzhiyun goto out;
74*4882a593Smuzhiyun }
75*4882a593Smuzhiyun
76*4882a593Smuzhiyun ret = scmi_dt_get_smt_buffer(dev, &chan->smt);
77*4882a593Smuzhiyun if (ret)
78*4882a593Smuzhiyun dev_err(dev, "Failed to get shm resources: %d\n", ret);
79*4882a593Smuzhiyun
80*4882a593Smuzhiyun out:
81*4882a593Smuzhiyun if (ret)
82*4882a593Smuzhiyun devm_kfree(dev, chan);
83*4882a593Smuzhiyun
84*4882a593Smuzhiyun return ret;
85*4882a593Smuzhiyun }
86*4882a593Smuzhiyun
87*4882a593Smuzhiyun static const struct udevice_id scmi_mbox_ids[] = {
88*4882a593Smuzhiyun { .compatible = "arm,scmi" },
89*4882a593Smuzhiyun { }
90*4882a593Smuzhiyun };
91*4882a593Smuzhiyun
92*4882a593Smuzhiyun static const struct scmi_agent_ops scmi_mbox_ops = {
93*4882a593Smuzhiyun .process_msg = scmi_mbox_process_msg,
94*4882a593Smuzhiyun };
95*4882a593Smuzhiyun
96*4882a593Smuzhiyun U_BOOT_DRIVER(scmi_mbox) = {
97*4882a593Smuzhiyun .name = "scmi-over-mailbox",
98*4882a593Smuzhiyun .id = UCLASS_SCMI_AGENT,
99*4882a593Smuzhiyun .of_match = scmi_mbox_ids,
100*4882a593Smuzhiyun .priv_auto_alloc_size = sizeof(struct scmi_mbox_channel),
101*4882a593Smuzhiyun .probe = scmi_mbox_probe,
102*4882a593Smuzhiyun .ops = &scmi_mbox_ops,
103*4882a593Smuzhiyun };
104